Buildings, such as houses, commercial buildings, and industrial buildings, are insulated to reduce the amount of energy required o heat or cool the building. Buildings may have gaps, cracks and seams where air can enter and escape. These leaks can decrease the overall comfort of a building by allowing unwanted moisture, drafts and noise to penetrate the building, and can significantly increase the amount of energy needed to heat or cool the building. Spray foam is one type of insulation that is used to insulate buildings. The foam is applied to a nozzle at a high pressure, such that the foam is sprayed away from the nozzle. This spraying allows the foam to be applied to large surfaces and spaces. Spray foam expands to coat and seal several types of surfaces and cracks. For example, spray foam can be used to fill voids and gaps between framing members and exterior sheathing.